Reduction of tailpipe emissions is a constant goal in the automotive industry. As the standards for emissions continue to decrease, technologies must continually improve to meet the standards. Tailpipe emissions based on current standards may need to be reduced to meet future regulations, such as SULEV30 (Super Ultra-Low Emission Level) and SULEV20. Hydrocarbon (HC) cold start emission is one challenge for emission reduction and many efforts have been focused on this area. The traditional approaches to reducing cost start HC emissions include developing catalysts that can warm up quickly and light-off at lower temperatures and optimizing engine cold start conditions to deliver heat to the catalyst as quickly as possible. However, even with very fast catalyst light-off, there are generally at least tens of seconds during cold start when the catalyst is not warm enough to convert any HC species. For the PZEV (Partial Zero Emission Vehicle) level emission standard, this amount of HC is important and may require additional development.